Sawfish Facts
Sawfish Biology
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Sawfish are unique elasmobranchs (the sharks, rays and skates) that possess a large toothed rostrum, or saw as it is commonly called. Sawfish are rays that inhabit nearshore waters in tropical, subtropical and warm-temperate regions of the world. The body is flattened and they spend much of their time lying on the sea bottom. They are able to breathe while lying on the bottom by drawing in water to their gills through spiracles (large holes located behind the eyes). Sawfish are often confused with sawsharks, which also have saws. However, sawfish are a species of ray and have their gills located on the underside of their bodies. Sawsharks are a shark and have their gills on the sides of their bodies. The rostrum, or saw, is used to catch and kill food. Small sawfish use the saw to grub on the bottom and uncover small crustaceans and fish. Large sawfish swim through schools of fish (jacks, mullet, ladyfish) and swipe the saw through the school, stunning or impaling fish. Sawfish have been observed wiping their saws on the bottom, removing fish that have been impaled on the teeth of the rostrum. |
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| In Florida, newborn sawfish are about 2 feet long. It is believed that males reach sexual maturity at 10-11 feet and females at 11-12 feet. The largest size normally observed is 18 feet.
Very little is known about the age and growth of sawfish, the litter sizes (believed to be 10-20 young), how often sawfish mate and bear young, and the mating and pupping seasons. It is known that shallow estuarine areas are important habitat that act as a protective nursery for small, young sawfish. |
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Sawfish Species Sawfish belong to the family Pristidae, within the order Pristiformes. There are seven recognized species of sawfish worldwide. Some species are very similar and research currently under way may show that there are really fewer species than now believed.
The genus Pristis has six currently recognized species that can be divided into two similar groups:
2. The Pectinata group - characterized by a non-tapering rostrum with many teeth (22-32 per side) and a reduced "preference" for freshwater (although they can still tolerate freshwater for extended periods). The distinction between these species is relatively well defined and these species should remain valid.
The genus Anoxypristis has one currently recognized species with a narrow saw and more flattened and triangular teeth on the rostrum than the other six species:
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U.S. Population History Early accounts of elasmobranch fauna along the East Coast of the United States and in the Gulf of Mexico reported that smalltooth sawfish were abundant in coastal and estuarine areas. They were so common that one account from the late 1800s reported a fisherman on the Indian River in Florida caught more than 300 sawfish in one season. Large sawfish are also known to have migrated north along the east coast during summer as far north as New York, but more frequently to the Carolinas. Today, however, the population of smalltooth sawfish in the United States has been severely depleted. A survey of the Indian River system published in the early 1980s reported that sawfish had probably been extirpated from that system, where they had once been so common. This scenario is repeated in most areas throughout the sawfish's historic range. Three factors have been important in the decline of the population: |
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Map courtesy of George Burgess (Florida Museum of Natural History)
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| Today, smalltooth sawfish are mostly found in the waters off Southwest Florida, especially the remote sections along the Everglades National Park, Ten Thousand Islands and Florida Keys. While it is difficult to estimate the exact numbers of sawfish remaining in U.S. waters, it is likely that the population has declined at least 95% since 1900, and most likely much more. |
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Conservation Efforts In response to the severe decline in the smalltooth sawfish population in the western Atlantic, the species has been listed as Critically Endangered by the World Conservation Union's Shark Specialist Group and included in the Red List of Threatened Animals. In 1992, Florida completely protected sawfish within state waters, establishing zero commercial and recreational fishing bag limits. In 1999, the Ocean Conservancy (then the Center for Marine Conservation) petitioned the National Marine Fisheries Service (NMFS) to protect the smalltooth and largetooth sawfish under the federal Endangered Species Act (ESA). In 2000, NMFS returned a finding that the petition contained information that may indicate the need for ESA listing and established a Status Review Team to review all information related to the status of sawfishes in U.S. waters. The status review team determined that the data indicated a need to protect the smalltooth sawfish population (there was no evidence found that the largetooth sawfish still exists in U.S. waters). In 2001, NMFS published a proposed rule to list the smalltooth sawfish as Endangered under the ESA and opened a 90-day public comment period. On April 1, 2003 the smalltooth sawfish was listed as Endangered under the ESA, making it the first elasmobranch to be included on the list. This listing under the ESA recognizes the depleted state of the population, provides better protection to the smalltooth sawfish and its habitats throughout the United States and establishes the framework for developing conservation actions to recover the species. A Smalltooth Sawfish Recovery Team was formed to develop a recovery plan to save the species from extinction. A Smalltooth Sawfish Recovery Implementation Team was then formed to monitor the recovery of the species. In June 2007, the Convention on International Trade in Endangered Species (CITES) granted trade protection to all species of sawfish, banning the international trade of sawfish and their saws and fins. Limited trade of live sawfish from Australia for public aquarium display is still allowed.
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